The notation used to represent IPv6 addresses. The 128 bits address is divided in 8 blocks of 16 bits. Each block is represented as an hexadecimal number and moves apart from next block by means of colon orthographic sign (:). Inside each block, zeros left placed are removed. An example of an IPv6 unicast address represented in hexadecimal notation is 3FFE:FFFF:2A1D:48C:2AA:3CFF:FE21:81F9.